Life Science 11 unit 3

Virus

A virus is a non-cellular particle made up of genetic material and protein that can replicate only inside living cells.

Nucleic acid core

is the genetic information for the virus. It can be either DNA or RNA , and can even be single stranded in some viruses.

bacteriophage

virus that invades bacteria and consists of a core of nucleic acid, a capsid, and a tail

lytic infection

process in which a host cell is invaded, lysed, and destroyed by a virus

lysogenic infection

process in which viral dna is inserted into the dna of a host cell where it can remain for many generations before becoming active

parasite

organism that survives by living and feeding either inside of or attached to outer surfaces of another organism, thus doing harm to the host

prophage

viral dna attached to a bacterial chromosome

pathogen

disease causing microorganism

retrovirus

type of virus that contains rna as its genetic information

antibiotic

drug or natural compound that can attack and destroy certain microorganisms

antibody

special protein that can bind to an antigen on the surface of a pathogen and help destroy it

antigen

foreign substance that induces an immune response and interacts wiht specific antibodies

immune system

bodys primary defense against disease causing microorganisms

interferon

protein that helps other cells resist viral infection

lysozyme

enzyme that breaks down the cell walls of many bacteria

vaccine

injection of a weakened or mild form of a pathogen used to produce immunity

fever

human bodys response to an infection that results in increased body temperature in an effort to kill pathogens with heat

phagocyte

white blood cell that engulfs and destorys microorganisms

prokaryote

single celled organism whose cells do not have a nucleus

phototrophic autotroph

organism that can trap the energy of sunlight and convert it to organic nutrients

bacterium

one celled prokaryote, chiefly parasitic or saprophytic

bacillus

rod shaped bacterium

binary fission

type of asexual reproduction in which an organism divides to produce 2 identical daughter cells

coccus

spherical bacterium

chemotrophic autotroph

organism that can obtain energy form inorganic molecules

chemotrophic heterotroph

organism that can obtain energy by taking in organic molecules and then breaking them down

spirillum

spiral shaped bacterium

obligate aerobe

organism that requires a constant supply of oxygen to live

obligate anaerobe

organism that lives only in the absence of oxygen

toxin

poison

facultative anaerobe

organism that can survive with or without oxygen

conjugation

process in bacteria and protists that involves an exchange of genetic information

endospore

type of spore formed when a bacterium produces a thick internal wall that encloses its dna and a portion of its cytoplamsm

unicellular

single celled organism, one cell does everything

saprophyte

organism that uses the complex molecules of a once living organism as its source of energy and nutrition